package org.dromara.demo.designPattern.ocp.service.impl;

/**
 * 遵守开闭原则的方式
 */
public class CalculationAreaExt extends CalculationArea{

    private final static double π = 3.141592653D;;

    @Override
    public double circular(double r) {
        return π * r * r;
    }
}
